Method and apparatus for installing anchors

ABSTRACT

A method and apparatus for installing an anchor utilize the rotational power and axial thrust from a mechanical power source. The novel method and apparatus are particularly adapted for installing an earth anchor of the type having at least one helical screw portion attached to a polygonally-shaped hub portion and having an elongated portion extending from the hub portion and include the placement of an elongated tube for telescopically receiving the elongated portion extending from the hub portion of the anchor in engagement with the hub portion. The drive tube includes a wrench engaging first end complementarily shaped to securely engage the polygonally-shaped hub portion of the anchor at least partially in the area of attachment of the helical screw portion to the hub portion to thereby transmit the rotational power from the mechanical power source to the anchor at an increased cross-sectional area of the anchor. The wrench engaging first end is further complementarily shaped to the pitch of the helical screw portion to engage a surface of the helical screw portion at a plurality of points to thereby distribute the axial thrust from the mechanical power source across a portion of the surface of the helical screw portion.

United States Patent 1 1,

J ahnke 1451 Sept.3, 1974 METHOD AND APPARATUS FOR INSTALLING ANCHORS [75] Inventor: Earl Milton Jahnke, Elmhurst, Ill.

[22] Filed: NOV. 17, 1972 [21] Appl. No.: 307,549

- [52] US. Cl 61/53.68, 52/157, 61/63,

Great Britain 61/53 Primary ExaminerJacob Shapiro Attorney, Agent, or Firm- Mason, Kolehmainen, Rathburn & Wyss [57 1 ABSTRACT A method and apparatus for installing an anchor utilize the rotational power and axial thrust from a mechanical power source. The novel method and apparatus are particularly adapted for installing an earth anchor of the type having at least one helical screw portion attached to a polygonally-shaped hub portion and having an elongated portion extending from the hub portion and include the placement of an elongated tube for'telescopically receiving the elongated portion extending from the hub portion of the anchor in engagement with the hub portion. The drive tube includes a wrench engaging first end complementarily shaped to securely engage the polygonally-shaped hub portion of the anchor at least partially in the area of attachment of the helical screw ortions thefhub portion to thereby transmit the rotational power from the mechanical power source to the anchor at an increased cross-sectional area of the anchor. The wrench engaging first end is further complementarily shaped to the pitch of the helical screw portion to engage a surface of the helical screw portion at'a plurality of points to thereby distribute the axial thrust from the mechanical power source across a portion of the surface of the helical screw portion.

15 Claims, 17 Drawing Figures PATENTED 3 974 SHEET 3 OF 5 FIG, 8 60 62 SHEET s 0? 5 PATENTED 3EP3 974 PAIENTED 1974 3,832,860 SHEEI 5 BF 5 METHOD AND APPARATUS FOR INSTALLING ANCHORS BACKGROUND OF THE INVENTION A. Field of the Invention The present invention relates generally to earth anchors and, more particularly, to a method and apparatus for installing such anchors in the earth.

8. Description of the Prior Art Anchors installed in the earth are commonly utilized to provide anchorage for supporting in tension or in compression electrical or mechanical hardware or equipment. For example, earth anchors are commonly utilized to provide anchorage for guy lines used to support electrical transmission, distribution and communication equipmentj Further, earth'anchors are used to provide support in compression for electrical and mechanical equipment, such as street lighting poles and other similar equipment. As the electrical transmission, distribution and communication equipment has increased in size, more forces are encountered on the guy lines; and, thus, a "need for greater anchorage has arisen. To provide greater anchorage, earth anchors have been developed which include helical screw portions having very large screw flange areas. Further, greater anchorage is achieved by providing a plurality of such helical'screw portions on a single anchor. As the anchorage capacity of earth anchors is increased, their installation becomes more difficult.

At one time, earth anchors were manually installed However, as anchors have been improved and their size increased, their manual installation has become increasingly difficult and, in some cases, impossible. Thus, in most cases, earth anchors are presently installed by the utilization of the rotational power and the axial thrust from a mechanical power source Typically, the mechanical power source comprises the power digging machines traditionally used in the construction of electrical transmission,.distribution and communica tion equipment for boring comparatively large diameter holes in the earth by means of auger type drill bits.

are improvements over the installation of an earth an-. chor by hand, they have severalserious disadvantages.

One such disadvantage is that themechanism for securely retaining an earth anchor within the installation apparatus is mechanically complex and has a tendency to jam under stress or continuous use. This jamming tendency renders the task of removing the installation apparatus from the installed earth anchor timeconsuming and arduous. l l

Another such disadvantage is that after installing an earth anchor by the use of the method and apparatus of the above-mentioned patents, an operator is'required to approach the equipment and physically release the mechanism for retaining the earth anchor within the installing device. Such a procedure proves to be time-consuming, expensive due to the added manual labor involved and hazardous in that under certain circumstances, the safety of the operator may be imperiled by his presence in the vicinity of the installation apparatus and by the necessity for him to physically handle the installation apparatus.

Another major disadvantage in the above-mentioned prior art method and apparatus is that in order to remove the installation apparatus from an installed earth anchor, an operator, on occasion, is required to rotate the installed anchor clockwise and counterclockwise andto apply a forward and reverse axial thrust in order to disengage the mechanism for retaining the earth anchor within the installation apparatus to thereby permit the separation of the installation apparatus from the installed earth anchor. Such a removal procedure seri-' ously disturbs the soil around the helical screw portion of an installed earth anchor and thereby reduces the anchorage capacity or holding strength of the installed anchor.

Another serious disadvantage in the use of the abovementioned prior art method and apparatus is the possibility that an operator of the installation apparatus may remove an installed earth anchor,-especially those anchors having relatively small helical screw portions, from the earth by inadvertently failing to disengage the mechanism used to securely retain the earth anchor within the installation apparatus.

Another major disadvantage is that, since'the telescoping tube of the above-mentioned prior art apparatus contacts an earth anchor merely over the hub portion, in the presence of high installation rotational power or'torque, the hub portion may shear separating the helical screw portion from the remaining portions of the earth anchor, thereby preventing the installation of a. unitary anchor in the earth.

A further serious disadvantage of the abovementioned prior art method and apparatus is the inability of the installation apparatus to provide an easy and rapid test of the holding strength of an installed earth anchor.

Another major disadvantage of the above-mentioned prior art method and apparatus is the use of a substantially square end on a drive tube for engaging the polygonally shaped hub portion of an earth anchor during the installation procedure. With the use of such a drive tube, the helical screw portion of an earth anchor is engaged at one point onthe trailing edge of the helical screw portion. During the application of the forward axial thrust required to install the earth anchor, such a drive tube concentrates the forward axial thrust at that one point of engagement on the trailing edge of the helical screw portion, thereby occasionally damaging the trailing edge of the helical screw portion. This damaged trailing edge of the helical screw portion has been found on many occasions to tear under loading intension or compression thereby reducing the anchorage capacity of the installed earth anchor.

Another series disadvantage of the above-mentioned prior art method and apparatus also results from the use of a square drive end for engaging the hub portion of an earth anchor during the installation procedure.

Since sucha drive end is capable of engaging the earth anchor onlyin its polygonally shaped hub portion, the earth anchor able towithstand without damage only a relatively limited amount of torsional and bending stresses. The torsional and bending stresses to which the earth anchor is subjected during the installation procedure are concentrated at the point of engagement of the polygonally shaped hub portion of the earth anchor with the square drive end. If the bending stress to which the earth anchor is subjected during the installation procedure is increased, for example, by the en'- gagement of the forward end of the earth anchor with a relatively fixed object, the amount of torsional stress able to be withstood by the earth anchor is correspondingly reduced. Therefore, the ability of earth anchors to withstand large amounts of torsional and bending stresses during the installation procedure is rather limited by the use of the above-mentioned prior art method and apparatus.

Further, another major disadvantage of the abovementioned prior art method and apparatus is the inability of an operator of the installation apparatus to continuously measure and monitor the applied forward axial thrust required to install an earth anchor. The continual measuring and monitoring of the applied forward axial thrust is desirable in order to avoid the churning of the soil which would result in a reduced anchorage capacity or holding strength of the installed earth anchor. v

Finally, another serious disadvantage of the abovementioned prior art method and apparatus results from nally shaped hub portion of the anchor at least partially in the area of attachment of the helical screw portion to the hub portion to enable the anchor to withstand severe torsional and bending stresses without shearing.

Another object of the present invention is the provision of a new and improved method and means for installing anchors of the type having at least one helical screw portion attached to a polygonally shaped hub portion and having an elongated portion extending from said hub portion into the earth by the utilization of the rotational power and the axial thrust from a mechanical power source including an elongated tubular means telescopically receiving the elongated portion extending from the hub portion of the anchor and having a first end adapted to securely engage the polygonally shaped hub portion ofthe anchor at least partially in the area of attachment of the helical screw portion to the hub portion and further adapted to securely engage the polygonally shaped hub portion of the anchor at least partially in the area of attachment of the helical screw portion to the hub portion on at least a plurality the varying soil conditions that may be encountered during an installation procedure whichmay cause the rotating helical screw portion of an anchor to provide a forward axial thrust much greater than that provided chine and its supporting mechanism. Thus, the installation of earth anchors by prior art methods and appara tus has proved to be, in many cases, expensive and time-consuming.

SUMMARY OF THE INVENTION An object of the present invention is the provision of a new and improved method and apparatus for installing earth anchors.

Another object of the present invention is the provision of a new and improved method and apparatus for rapidly installing earth anchors and especially adapted for rapidly installing earth anchors of the type having at least one helical screw portion attached to a polygonally shaped'hub portion and having an elongated portion extending from the hub portion.

Another object of the present invention is the provision'of a new and improved method and apparatus for installing earth anchors of the type having at least one helical screw portion attached to a polygonally shaped of sides of the polygonally shaped hub portion of the anchor to enable the anchor to withstand and severe torsional and bending stresses occuring during an installation procedure without shearing.

' Another object of the present invention is the provision of a new and improved method and means for engaging an earth anchor along a portion of the surface of its helical screw portion to thereby apply a distributed forward axial thrust for installing the anchor into the earth to prevent damage to the helical screw portion resulting from 'the conventional application of an axial thrust concentrated at a single pointalong the helical screw portion.

Briefly, the above andother objects of the present invention are achieved by a new and improved method and apparatus for installing anchors in the earth by the utilization of the rotational power and the axial thrust from a mechanical power source and especially adapted for installing anchors of the type having at least one helical screw portion attached to a polygonally shaped hub portion and havingan elongated portion extending from the hub portion. The installation apparatus includes an elongated drive tube connected to the mechanical power source and adapted to telescopically receive the elongated portion extending from the hub portion of the anchor. The drive tube includes a wrench engaging first end complementarily shaped to securely engage the polygonallyshaped hub portion of the anchor advantageously at least partially hub portion and having an elongated portion extending from said hub portion into the earth by the utilizationin the area of attachment of the helical screw portion to the hub portion to transmit the rotational power from the mechanical power source to-the anchor. By

engaging the anchor in the areaof attachment of the helical screw portion to the hub portion, the drive tube utilizes the increased cross-sectional area of the anchor at that specific portion of the anchor to enable the anchor to withstand the application of a very high rotational power or torque from the mechanical power source without shearing and to withstand the severe torsional and bending stresses encountered during an installation procedure.

Advantageously, the wrench engaging first end of the drive tube is also complementarily shaped to the pitch of the helical screw portion to enable the engagement of the helical screw portion by thedrive tube along a portion of the surface of the helical screw portion. Such an engagement distributes the applied forward axial thrust from the mechanical power source along a portion of the surface of the helical screw portion rather than concentrating the applied axial thrust at a single point of the surface of the helical screw portion.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects and advantages and novel features of the present invention will become apparent from the following detailed description of a preferred embodiment of the invention as illustrated in the accompanying drawings wherein:

FIG. I is a front, elevational view of a preferred embodiment of a novel apparatus for installing an earth anchor embodying features of the present invention;

FIG. 2 is a fragmentary, front, elevational view of the separation of the novel installation apparatus of FIG. I from an installed earth anchor in -accordance with the principles of the present invention;

FIG. 3 is a front, elevational view of an earth anchor installed in accordance with the principles of the pres ent invention; 1

FIG. 4 is an enlarged, cross-sectional view of a portion of the novel apparatus of FIG. 1 taken long line 44 of FIG. I;

FIG. 5A is an enlarged, fragmentary, partially crosssectional and partially elevational view of a portion of the novel apparatus of FIG. 1 taken along line 5-5 of FIG. 4;

FIG. 5B is an enlarged, fragmentary, partially crosssectional and partially elevational view of the lowermost portion of the novel apparatus of FIG. 1 taken along line 5-5 of FIG. 4;

FIG. 6 is an enlarged, cross-sectional view of a portion of the novel apparatus of FIG. 1 taken along line 6-6 of FIG. 5A;

FIG. 7 is an enlarged, cross-sectional view of a .portion of the novel apparatus of FIG. 1 taken along line 77 of FIG. 5A;

. I 6 novel apparatus of FIG. 1 taken along line 55 of FIG.

FIG. 15 is an enlarged, cross-sectional view of a portion of the device of FIG. 14 taken along line 15-l5 of FIG. 14; and

FIG. 16 is an enlarged, fragmentary, detail view in cross-section of a portion of the device of FIG. 14 taken along line'16l 6 of FIG. 15.

DESCRIPTION OF THE PREFERRED EMBODIMENT.

1. General Description Referring to the drawings and initially to FIG. 1, there is illustrated a new and improved apparatus for installing anchors into the earth generally designated as 20 and constructedin accordance with the principles of the present invention. The installation apparatus 20 serves to rapidly install an anchor into the-earth and thereafter to rapidly separate the installation apparatus 20 from the installed anchor.

In accordance with an important advantage of the present invention, the installation apparatus 20 is especially adapted for installing an anchor 22 into the earth or ground 24 by the utilization of the rotational power and the axial thrust from a mechanical power source 26. As used herein, the word earth is intended to designate any substance or medium into which an anchor 22 may be placed. For example, the word earth of a portion ofthe novel apparatus of FIG. I taken from line ll-ll of FIG. 9; 1

FIG. I2 is an enlarged, fragmentary, elevational view of a portion of the novel apparatus of FIG. 1 taken from line l2l2 of FIG. 9;

FIG. 13 is an enlarged, fragmentary, exploded, per- I view of an alternate embodiment of a portion of the would include an ice layer, an ocean bed or oneor more soil layers. The mechanical power source 26 preferably includes a boom arm 28 for supplying the forward axial thrust required to install an anchor 22 into the earth 24 and for supplying the reverse axial thrust required to separate the installation apparatus 20 from an installed earth anchor 22. The mechanical power source 26 in a preferred embodiment further includes a source of rotational power29. The source of rotational power 29 may be a hydraulic, pneumatic or electrical torque motor. The boom 28 conventionally extends from a truck (not shown) to provide the desired mobility for the mechanical power source 26.

The anchor 22 in the embodiment depicted in FIG. 1 includes a helical screw portion 30 attached to a polygonally shaped hub portion 32 and an elongated portion 34 extending from the hub portion 32. In the embodiment of FIG. 1, the elongatedportion 34 comprises a guy'rod. I

The installation apparatus 20 includes an elongated drive tube 36 adapted to telescopically receive the elongated portion 34 extending from the hub portion 32 of the anchor 22. In accordance with an important advantage of the presentlinvention, the drive tube 36 preferably includes a wrench engaging first end 38 complementarily shaped to securely engage the polygonally shaped hub portion 32 of the anchor 22 at least partially in the area of attachment 40 of the helical screw portion 30 to the hub portion 32'to thereby more cffectivelytransmit the rotational power from the mechanical power source, 26 to the anchor 22. By engag ing the. anchor 22 in the area of attachment 40,. the installation apparatus 20 utilizes the increased crosssectional area of that specific portion of the anchor 22 to enable the anchor 22'to withstand the'ap'plication of a very high rotational power or torque from the mechanical power source 26 without shearing. Since the anchor 22 is adapted to withstand the application of very high rotational power or torque from the mechanical power source 26, the anchor 22 may thus be installed in mediums which previously caused the shearing of anchors 22 at their hub portions 32.

Furthermore, it is occasionally found that during an installation procedure, the hub portion 32 may tend to radially deform or twist in response to torsional stresses. In accordance with an important feature of the present invention, under such circumstances, the wrench engaging first end 38 engages the surface of the trailing edge of the helical-screw portion 30 lying generally parallel to the longitudinal axis of the anchor 22 to positively engage and rotatably drive the helical screw portion 30 in addition to engaging and driving the hub portion 32. By such a novel engagement, the torsional stresses in the hub portion32'are relieved and the installation of the anchor 22 into mediums which previously may have caused the shearing of the hub portion 32 is accomplished. a

in accordance with an important feature of the present invention, by engaging the polygonally shaped hub portion 32 of the anchor 22 in the area of attachment 40 of the helical screw portion 30 to the hub portion 3 2, the capacity of an anchor 22 to withstand severe tions 54 enable the installation apparatus to be operated by relatively inexperienced and unskilled persontorsional and bending stresses during an installation procedure is greatly increased. By such an engagement of an earth anchor 22 by the installation apparatus 20, the torsional and bending stresses arising during an installation procedure are concentrated at an increased cross-sectional area of an earth anchor 22, that is, throughout the cross-sectional area of the polygonally shaped hub portion 32 and of the helical screw portion 30 of the anchor 22. Thus, an earth anchor 22 installed in accordance with the principles of the present invention is capable of withstanding torsional and bending stresses which formerly would have damaged or destroyed by'shearing the hub portion 32 of an anchor 22.

In accordance with a further important feature of the present invention, the wrench engaging first end 38 of the drive tube 36 is complementarily shaped to the pitch of the helical screw portion 30 to engage the helical screw portion 30 along a portion of its surface. By so engagingthe helical screw portion 30, the drive tube 36 distributes the applied forward axial thrust required to install an anchor 22 into the earth 24 along a portion of the surface 30 rather than concentrate the applied forward axial thrust at a single point of the surface of the helical screw portion 30. Thus, the possibility of damage to the trailing edge of the helical screw portion 30 during an installation procedure is greatly reduced.

and, in most cases, eliminated. I

in accordance with a further advantage of the present invention; the installation apparatus 20 includes an adapter 50 for connecting the drive tube 36 to the mechanical power source 26. In accordance with an important feature of the present invention, the adapter 50 includes a force transducer 52 comprising a spring and spline assembly or measuringand indicating the axial thrust applied to the anchor 22 by the mechanical power source 26 and for transmitting the rotational power and axial thrust from the mechanical powersource 26 to the drive tube 36 for application to the anchor '22. The force transducer 52 preferably includes visual means or designations 54 for indicating when the preferred axial thrust isbeing applied by the mechanical power source 26 through the installation apparatus 20 to the anchor 22 to thereby aid an operator in the nel.

The adapter 50 further includes an adapter portion 56 for connecting the installation apparatus 20 to a polygonally shaped rotatable output shaft 58 of the mechanical power source 26. The adapter 50 also includes an adapter portion 60 for connecting the drive tube 36 to the force transducer 52. The adapter portion 60 is designed to receive and securely retain a second, longitudinal end 62 of the drive tube 36, The adapter portion 60 further includes a pair of bolts 64 receivable through a pair of apertures in the end 62 of the drive tube 36 for lockingly engaging and securely'retaining the drive tube 36 within the adapter portion 60. The adapter portion 60 also includes an aperture 66 for re ceiving a shear pin 67 used to retain the anchor 22 within the installation apparatus20. I

The anchor 22, illustrated in FlG.'1, is positioned at a desired angle with respect to the surface of the earth 24 for installation by the installation apparatus 20. in

order to install the anchor 22 into the earth 24, an opchanical power source 26. In the event of a deviation from the proper axial thrust, the operator may increase or decrease the axial thrust from the mechanical power source 26 as required to maintain the proper amount of axial thrust during the installation procedure.

After the anchor 22 has been inserted to a desireddepth in the earth. 24,'the installation apparatus 20 may be removed from the anchor 22 by an axial thrustfrom the mechanical power source 26 in a direction opposite to that utilized to install the anchor 22 into the earth 24 (FIG. 2). This axial thrust in a opposite or reverse direction must be of a sufficient magnitude to shear the shear pin 67 in the aperture 66 of the adapter portion 60. The shearing of the shear pin 67 releases a shear pin coupling 68 attached to the anchor 22 from its position within a complementarily shaped recess 70; in the adapter portion 60 freeing the anchor 22 for removal from the installation apparatus 20. Alternately, after the installation of the anchor 22 into the earth 24, an operator could simply remove the shearpin 67 from the shear pin coupling 68 to permit the simple subsequentseparation and removal of the installation apparatus 20from the installed earthanchor 22.

After the installation apparatus 20 has been removed from the installed anchor 22, the shear pin coupling 68 may be removed and replaced by a suitable eyelet 72' (FIG. 3) to which a guy wire may then be attached.

. supplied by the mechanical power source 26 and includes the rotational power from the power source 29 and the axial thrust from the boom 28. The rotational power and axial thrust flow from the mechanical power source 26 through the adapter portion 56, the force transducer 52, the adapter portion 60, and the drive tube 36 to the hub portion 32 of the anchor 22. The rotational power and axial thrust are transferred from the installation apparatus 20 to the anchor 22 at the hub portion 32 to enable the anchor 22 to be installed to a desired depth in the earth 24.

As illustrated in FIG. 4, the installation apparatus 20 is connected to the mechanical power source 26 through the adapter portion 56. The adapter portion 56 includes a longitudinally extending, tubular wallportion 75 complementarily shaped to the polygonally shaped rotatable output shaft 58 of the power source 29 to thereby receive and securely engage the output shaft58. The wall portion 74 and the output shaft 58 include aligned, transverse apertures 78 for receiving a bolt or pin coupling 80 used to lock the output shaft 58 and the wall portion 74 together. Preferably, the bolt 80 includes an aperture 82 for receiving a hitch pin clip or a cotterpin to thereby securely retain the pin 80 in the apertures 78.

Although the output shaft 58 has been illustrated as a male shaft and the wall portion 74 illustrated as a female receptacle, the output shaft 58 of the power source 29 may, in a particular embodiment, comprise a female receptacle for receiving a complementarily polygonally shaped male coupling on the adapter portion 56. Further, although the output shaft 58 and wall portion 74 are illustrated as being hexagonally shaped, other polygonall y shaped output shafts 58 and wall portion 74 may be utilized.

The adapter portion 56 further includes a plurality of bolts 90 for fastening the adapter portion 56 to the force transducer 52. Other suitable fastening means may be used to couple the adapter portion 56 to the force transducer 52. Altemately, the adapter portion 56 may be integrally formed with the force transducer 52.

From the adapter portion 56, the rotational power and axial thrust required to install an anchor 22 into the earth 24 flows into and through a force transducer'52 (FIG. A). In accordance with an important advantage of the present invention, the force transducer 52 includes a spring assembly 92 and a spline assembly 94.

' The spring assembly 92 comprises an elongated-spring 100. As the axial thrust is applied by the mechanical mally arising during a typical installation procedure to thereby achieve a smooth installation of the anchor 22 (FIG. 1) in the earth 24.

The rotational power from the mechanical power source 26 is transferredthrough' the force transducer 52 (FIG. 5A) to the adapter portion 60 by the spline assembly 94. The spline assembly 94 includes an elon' gated shaft orplunger 108 having a plurality of splines 110 (FIGS. 5A and 6). The specific number of splines 110 will depend upon the rotational power or torque capacity required or to be transferred through the installation apparatus 20. The elongated shaft 108 is movable within a chamber 112 formed by an elongated, tubular member or spline housing 114. One end 1 16 of the tubular member 1 14 formes a splined shoulder portion complementarily shaped to the shaft 108 to securely engage the shaft 108 upon the application of rotational power to the force transducer 52 to enable the tubular member 114 to rotate with the shaft 108.

The shaft 108 is terminated at one end by a shoulder portion 118 for retaining the shaft 108 within the chamber 112. Preferably, resilient members 120 are positioned on either side of the shoulder portion 118 to absorb the shock resulting from the shoulder 118 arriving at its upper and lower limit positions, formed, respectively, by the end 116 of the elongated, tubular member 114 and the lower shoulder 100.

Since the elongated, tubular member 114 and the adapter'portion are securely attached to the lower shoulder of the force transducer 52 through a bolt assembly 122, the rotational power passing through the force transducer 52 is applied to the adapter portion 60.

The adapter portion 60 includes an elongated recess or chamber complementarily shaped to and securely retaining the longitudinal end 62 of the drive tube 36. The end 62 of the drive tube 36 includes a plurality of apertures 132 for receiving one or more bolts 64 to lockingly engage and securely retain the drive tube 36 within the adapter portion 60. By this engage- "ment, the adapter portion 60 transfers to the drive tube 36 the rotational power and axial thrust from the mechanical power source 26, the adapter portion 56 and the force transducer 52. 7

As is apparent from F IGS. 1 and 5A, the adapter portions 56 and 60 could,in-an alternate embodiment, be directly connected together should the force transducer 52 not be required or desired during a particular installation of an anchor 22 into the earth 24. Also, as

' is obvious, in a further'alternate embodiment, the

power source 26, the spring member 96 (FIG. 5A) is compressed between the shoulders. 98 and 100 and the housing 102 is telescopically received within the housing 106 in an amount proportional to the applied axial thrust. The outer surface of the housing, 102 includes,

adapter portions 56 and 60 could be formed as an integral unit in the absence of the force transducer 52.

1 The adapter portion 60 further'includes ana'perture 66 for receiving the shear pin 67.ln accordance with an important feature of the present invention, the shear pin 67 is utilized to retain theanchor 22 within the installation apparatus'20 during the installation procedure. Theshear pin 67 is received in an aperture 66 of the adapter portion 60 and an axially aligned aperture 136 in the shear pin coupling 68. Since the shear pin coupling 68 issecurely attached to the elongated por-' serting only one end of the shear pin 67 into the shear pin coupling 68, the single shear mode of the shear pin 67 is utilized in that the shear pin 67 is required to be severed at only one point in order to release the shear pin coupling 68 from the installation apparatus 20. If the shear pin 67 is positioned in the installation apparatus so that it passes completely through the shear pin coupling 68, the double shear mode of the shear pin 67 is utilized in that, in order to release the shear pin coupling 68 from the installation apparatus 20, the shear pin 67 must be sheared at two points. When used in its double shear mode, approximately twice the amount of energy .in the form of reverse axial thrust is required from the mechanical power source 26 in order to completely shear the shear pin 67 than is required if the shear pin 67 were utilized in its single shear mode.

The shear pin 67 may be held securely in place within the apertures 66 and 136 by any suitable means. For example, a retaining bolt or spring plunger 138 (FIG. 7) may be screwed into engagement with the shear pin 67 through a threaded recess 140 in the adapter portion 60.

The shear pin 67 performs other functions besides merely retaining the anchor 22 within the installation equipment 20. In accordance with an important advantage of the present invention, the shear pin 67 is designed to shear in an overload situation during an anchor installation procedure to thereby protect the power source 29 (FIG. 1) and the boom 28 from damage or destruction.

Anchors 22 occasionally encounter varying soil conditions during their installation in the earth 24. When this occurs, a situation may arise wherein the rotating helical screw portion may provide a forward axial thrust much greater than that provided by the mechanical power source 26 to thereby pull .the anchor 22, the installation apparatus 20, the power source 29 and the boom 28 rapidly forward towards the earth 24, possibly damaging or destroying the power source 29, the boom 28 or both. To prevent this situation from occurring, the shear pin 67 shears when the forward axial thrust provided by the rotating helical screw portion 30 exceeds the axial thrust provided by the mechanical power source 26 by an amount equal to or greater than the shear strength of the pin 67. Whenthe shear pin 67 shears in such a situation, the anchor 22 is released from the installation apparatus 20 to prevent the forward axial thrust provided by the rotating helical screw portion 30 of the anchor 22 from being transmitted to the installation apparatus 20, the power source 29 and the boom 28.

In accordance with a further important feature of the present invention, the installation apparatus 20 may be easily and rapidly removed from an installed anchor 22 by a reverse axial thrust from the mechanical power source 26 in a direction opposite to that of the forward axial thrust used to install the anchor 22 into the earth 24. The reverse axial thrust from the mechanical power source 26 must be of an amount equal to or greater than the shear strength of the shear pin 67. This rapid and easy separation of the installation apparatus 20 from an installed earth anchor 22 greatly reduces the time formerly required to complete the installation of an anchor 22 into the earth 24.

Further, the use of the shear pin 67 to retain the anchor 22 in the installation apparatus 20 eliminates the requirement for an operator to approach and physically contact the installation apparatus 20 in order to disengage the locking mechanism conventionally utilized in the prior art to retain the anchor 22 within the installation apparatus 20. In addition, the use of a shear pin 67 eliminates the possibility of an inadvertent removal of an installed earth anchor 22 from the earth 24 by the failure of an operator to release the locking mechanism conventionally used in the prior art. Also, by merely requiring a reverse axial thrust from the mechanical power source 26 to shear a shear pin 67 to separate the installation apparatus 20 from an installed earth anchor 22, the procedure occasionally required by the use of prior art installation devices of alternately rotating an installed earth anchor 22 clockwise and counterclockwise and of alternately applying a forward and reverse axial thrust in order to disengage the mechanism for re-. taining the earth anchor 22 within the installation device is eliminated. Thus, the reduction in the anchorage capacity or holding strength of an installed earth anchor 22 by the disturbance of the soil around the helical screw portion 30 of an earth anchor 22 during such a removal procedure is eliminated.

The separation'of the installation apparatus 20 from an installed earth anchor 22 accomplishes at least two other important functions. First, by requiring the shear pin 67 to be shearedbefore the separation of the installation apparatus 20from an installed anchor 22 can occur, the installed anchor 22 is thereby tested for its holding strength. Due to the inability of installers to accurately predict the precise holding strength of an anchor 22 in every installation location, a test of the holding strength of an installed anchor 22 is usually required after the installation procedure. This test, in accordance withthe principles of the present invention, is easily and rapidly performed during the separation of the installing apparatus 20 from an installed anchor 22. Since the particular holding strengths required for different installed anchors 22 may vary depending upon the loads to which the anchors 22 are expected to be subjected, the shear pins 67 utilized to retain the anchors 22 within the adapter portions 60 (FIG. 5A)

should be chosen so that their shear strengths are sufficient to provide an adequate test of the holding strengths of the installed anchors 22.

During a particular installation procedure, it may be found necessary or desirable to use a different shear pin 67 to test the holding strength of an installed anchor 22 than the shear pin 67 utilized to install the anchor 22 into the earth. In such a situation, after the installation of an anchor'22 into the earth .24, an operator may release the retaining bolt or spring plunger 138, remove the shear pin 67 used'during the installation procedure and substitute therefor adifferent shear pin 67 fortesting the holding strength of an installed anchor 22. Al-. 'temately, in such a situation, it may be sufficient for an operator to merely change the shear pin 67 from its use in its single shear mode of operation to a position in the adapter portion 60 in which its double shear mode of operation is utilized.

Secondly, since an'installed anchor 22 is tensioned by the reverse axial thrust applied to shear the shear pin- 67 during the separation of the installation apparatus 20 from the installed anchor 22, each installed anchor 22 is thereby set in the earthin that the soil normally disturbed around the helical screw portion'30 during the installation procedure i'slconsolidated and compacted by the tensioning of the installed anchor 22 dur- 'ing the separation procedure.

chamber 130 are designed to closely correspond to and just slightly exceed the outer dimensions of the end 62 of the drive tube 36 so as to reduce any movement or play of the drive tube 36 within the adapter portion 60 to a minimum. The drive tube 36 further includes a plurality of transverse, radially aligned apertures 132 to thereby enable the elongated tube 36 to be securely engaged by the bolts 64 notwithstanding the radial orientation of the drive tube 36 upon its receipt within the adapter portion 60.

Similarly, the inner dimensions of the recess 70 closely correspond to and are just slightly greater than the outer dimensions of the shear pin coupling 68 to thereby reduce any movement or play of the shear pin coupling 68 within the adapter portion 60 a a minimum. The shear pin coupling 68 further similarly includes a plurality of transversely aligned apertures 136 positioned so as to enable the shear pin coupling 68 to receive the shear pin 67 anclv to thus be securely retained within the adapter portion 60 notwithstanding the radial orientation of the shear pin coupling 68 upon its receipt in the recess 70.

The recess 70 further includes at its lower end tapered wall portions 142 to aid in the easy insertion of the shear pin coupling 68 in the recess 70. The tapered wall portions 142 act as a guide to direct the leading edges of the shear pin coupling 68 easily into the recess 70. The recess 70 in the adapter portion 60 further includes at its lower extremity shoulder portions 144 to act as stops in limiting the upward movement of the drive tube '36 within the aperture portion 60. As illustrated in FIG. A; the shear pin coupling 68 may include threaded recesses 146 of different diameters at opposite ends of the shear pin coupling 68 to enable the shear pin coupling 68 to accommodate elongated portions 34 of different diameters.

The rotational power and axial thrust required to install an anchor 22 (FIG. 1) into the earth 24 passes from the adapter portion 60 (FIG. 5A) to the drive tube 36 for application to the anchor 22 at its hub portion 32 (FIG. 5B). In accordance with an important advantage of the present invention, the wrench engaging end 38 of the drive tube 36 is complementarily shaped to securely engage the polygonally shaped hub portion 32 of the anchor 22 at least partially in the area of attachment '40 of the helical screw portion 30 to the hub portion 32 to more effectively transmit the rotational power from the mechanical power source 26 to the anchorv 22. This novel engagement of a polygonally shaped hub portion 32 of an anchor 22 by the drive tube 36 of the present invention may be readily appreciated by reference to the several viewsof this engagement depicted in FIGS. 58 and 9 through 12.

By engaging the anchor 22 in the area of attachment of the helical screw portion 30 to the hub portion 32, the drive end 36 of the installation apparatus takes advantage of the increased mechanical stiffness of the anchor 22 due to the increased cross-sectional area at that specific portion of the anchor 22 to enable the anchor 22 to withstand the application of a very high rotational power or torque from the mechanical power source 26 without shearing.

Further, since the engagement of the installation apparatus 20 with the anchor 22 takes place at an increased cross-sectional area of the anchor 22, the anchor 22 is able to withstand much greater torsional and bending stresses without shearing than earth anchors 22 installed according to conventional prior art methods and devices.

Also, in accordance with an important feature of the present invention and as clearly illustrated in FIGS. 5B and 9 through 12, the wrench engaging first end 38 of the drive tube 36 advantageously is complementarily shaped to follow the pitch of the helical screw portion 30 and to engage the helical screw portion 30 along a.

portion of its surface to thereby distribute the forward axial thrust required to install the anchor 22 into the earth along a portion of the surface of the helical screw portion 30. This novel engagement reduces the possibility of damaging the trailing edge of the helical screw portion 30 by the conventional engagement of the helical screw portion 30 by a square drive end at one point of the trailing edge of the helical screw portion 30 in accordance with prior art methods and devices.

Further, as is clearly illustrated 'in FTGS. 5B and 12, the wrench engaging end 38 of the drive tube 36 may, on occasion, engage a surface 147 of the helical screw portion 30 to apply the rotational power from the power source 29 directly to the helical screw portion 30 and to thereby relieve a portion of the torsional stress in the hub portion 32 of an anchor 22 during an installation procedure. The wrench engaging first end 38 is further graphically illustrated in FIG. 13 wherein an enlarged, fragmentary, exploded, perspective view of several of the individual components of the installation apparatus 20 described above is set forth. In assemblying the component parts of the installation apparatus 20 in accordance with the principles of the present invention, the drive tube 36 is inserted into the recess or chamber until the longitudinal end 62 of the drive tube 36 is stopped by the shoulder portions 144. In this position, two of the apertures 132 in' the drive tube 36 are aligned with a plurality of apertures 148 in the dapter portion 60 for receiving the bolts 64. The bolts 64 are inserted in the apertures 148 until two end portions of the bolts 64 are received withintwo of the apertures 132 of the drive tube 36 to thereby securely retain the drive tube 36 within the recess or chamber 130.

In order to insert and securely retain the anchor-22 within the installation apparatus 20, the shear pin coupling 68 is attached to one end of the elongated portion 34 of the anchor 22. One suitable manner of attachment is by the reception of a threaded end 152 of the elongated portion 34 of the anchor 22 within the threaded recess -146-in one longitudinal end of the shear pin coupling 68. After the shear pin coupling 68 is attached to the anchor 22, the anchor 22 is inserted into the installation apparatus 20 by passing the shear pin coupling 68 and the end portion 34 through the drive tube 36 and into the adapter portion 60. The shear pin coupling 68 is guided into its at rest position within the recess 70 by the tapered wall portions 142. In this position, the shear pin 67 is inserted through the apertures 66 and 136 and is securely retained inits normal operating position (FIG. 5A) by the retaining bolt or spring plunger 138 (FIG. 13).

The apertures 136 in the shear pin coupling 68 are elongatedaxially in order to enable the shear pin 67 to be received therethrough irrespective of slight differences in the lengths of different anchors 22. The coupling 68 is preferably designed so as not to engage the closed longitudinal end of the recess 70. Such an engagement would in many cases, cause the elongated portion 34 to buckle in the drive tube 36. Thus, the distance between each longitudinal end of the elongated aperture 136 (FIG. 13) and the more distant end of the two longitudinal ends of the shear pin coupling 68 is less than the distance between the elongated aperture 66 in the adapter portion 60 and the closed longitudinal end of the recess 70. By maintaining these dimensional relationships, the axial force from the mechanical power source 26 (FIG. 1) is applied by the drive tube 36 to the helical screw portion 30 of the anchor 22 to thereby drive the anchor 22 into the earth 4.

3. Modifications Obviously, many modifications and variations of the present invention are possible in light of the above teachings. For example, an alternate embodiment of the force transducer 52 (FIG. 5A) constructed in accordance with the principles of the present invention is a force transducer 158 (FIGS. 14 through 16). The force transducer 158 may be used for those installation procedures in which the forward axial thrust applied to an anchor 22 must be precisely controlled and monitored. The force transducer 158 effectively reduces the loss ofa portion of the forward axial thrust in overcoming the friction forces present in the transducer 52 (FIG. 5A) and thus enables the visual designations 54 (FIG. 14) to more accurately indicate the forward axial thrust being applied to the anchor 22.

The force transducer 158 includes a spring assembly 92 and a spline assembly 160. The spring assembly 92 of FIG. l4'differs from the spring assembly 92 of FIG. 5A only in that the elongated springmember 96 (FIG. 14) is compressed between a shoulder 98 and a spline housing flange 162 preferably integrally attached to an elongated, tubular member or spline housing 164.

In accordance with an important feature of the present invention, the spline assembly 160 includes a ball bearing spline 166 securely fastened to one end or a shoulder portion 168 of the housing 164. The ball bear ing spline 166 reduces to a minimum the amount of the forward axial thrust lost through the frictional engagement of the shaft 108 (FIG. 5A) with the end 116 ofthe tubular member or spline housing 114. Thus, the ball bearing spline 166 (FIG. 14) permits the forward axial thrust to be monitored quite closelyand to be quite accurately indicated by the visual designations 54 (FIGS. 1 and 14).

The spline assembly 160 includes an elongated shaft or plunger 170 having a plurality of splines 172. The shaft 170 preferably includes a plurality of inner concave races 174 for receiving a plurality of ball bearings 176 positioned in a plurality of outer concave races 178 that mate, with the races 174 and are positioned within the shaft 170 and the spline 166 are axially displaced relative to each other.

Preferably, the shaft 170 is terminated atone end by a member or shoulder portion 182'for retaining the shaft 170 within a chamber 184 of the housing 164. Resilient members 186 are positioned on either side of the shoulder portion 182 to absorb the shock resulting from the shoulder portion 182 arriving at its upper and lower limit positions, formed, respectively, by the end 168 of the tubular member or housing 64 and the lower shoulder 100. Further, a thin metallicor hard nylon washer 188 may be utilized to reduce the wear on the upper resilient member 186 in contacting the shoulder portion 168 at the upper limit position of the shaft 170.

At the other end of the shaft 170, a polygonally shaped, longitudinally extending portion 190 integrally connected to the shaft 170 is provided for mating with and reception in a complementarily shaped recess 192 in the shoulder 98 for transferring the rotational power from the shoulder 98 tothe shaft 170. Further, the shaft 170 may include a threaded, longitudinally extending portion (not shown) integrally attached to the portion 190 and received within a complementarily shaped and threaded recess (not shown) in the adapter portion 56 for securely retaining the portion 190 in the recess 192 to thereby maintain the shaft 170 in engage ment with the shoulder 98. In assembling the shaft 170, the shoulder 98 and the adapter portion 56, one longitudinal end of the splined portion of the shaft 170 is brought into engagement with the shoulder 98 such that the portion 190 is fully received within the recess 192. The threaded, longitudinally extending portion of the shaft 170 may then be received within the complementarily shaped and threaded recess of the adapter portion 56 by rotating the adapter portion 56, the shaft 170 and the shoulder 98 or the force transducer 158, until the threaded portion of the shaft 190 is fullyreceived within the complementarily shaped and threaded recess of the adapter portion 56. The bolt assembly may then be secured in place to retain the adapter portion 56, the shoulder 98 and the shaft 170 in a secure engagement.

Preferably, the flange 162 is securely fastened to the shoulder by a bolt assembly 194. The shoulder 100 may be attached to the adapter portion 60 by means of a bolt assembly 196. The housing 106 may be securely fastened to the flange 162 by a set screw-assembly 197. Y

The ball bearing spline 166 may be securely attached to the end 168 of the housing 164 by means of a set screw assembly or a key and set screw assembly 198. A bolt assembly 199 may be utilized to secure the shoulder portion 182, the upper resilient member-186 and the washer 188 to the shaft 170. Finally, a recessed bolt assembly 200 isv preferablyutilizedto-secure-the' lower resilient member l86 to the shoulder portion 182.

Further, a particular earth anchor 22 (FIG. 1) mayv I tension of the hub portion 32.

clude an end 62 receivable within theadapter portion 60 for securely retaining the drivetube 36 as an Inte gral part of the installation apparatus 20 and a wrench engaging first end 38 for engaging the hub portion 32 of such an anchor 22 in the area of attachment 40 of the uppermost helical screw portion 30 to the hub portion 32.

Also, instead of merely providing anchorage for a guy line, the anchor 22 (FIG. 1) may be utilized as a support for street lighting poles or other similar equipment. In such an application, the elongated portion 34 may comprise a hollow or solid, tubular, elongated member extending from the hub portion 32. The uppermost endof such an elongated member would be modified, for example, by the attachment thereto of a support plate, to serve as an attachment and support means for a street lighting pole or other similar quipment. equipment.

Furthermore, the elongated portion 34 of an anchor 22 and the drive tube 36 may in a particular embodiment be required to be extended in length by including a plurality of similar such elements suitably coupled together in order to install the anchor 22 to a desired depth in the earth 24. Thus, it is to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically de-' scribed.

What is claimed and desired to be secured by Letters Patent of the United States is:

1. A device for installing an anchor of the type having at least one helical screw portion attached to a polygonally shaped hub portion and having an elongated portion extending from said hub portion, in the earth by the utilization of rotational power and axial thrust from a mechanical power source comprising an elongated tubular means for housing said elongated portion of said anchor and having a first end adapted to securely engage said polygonally shaped hub portion of said anchor in a driving engagement and further adapted to engage said hub portion at least partially in the area of attachment of said helical screw portion to said hub portion, said first end including means for engaging said polygonally I shaped hub portion in a driving engagement at least partially in the area of attachment of said helical screw portion to said polygonally shaped hub portion.

2. A device as defined in claim 1 wherein said first end of said elongated tubular means is adapted to contact a surface of said helical screw portion on a plurality of sides of said polygonally shaped hub portion.

3. In combination, ananchor of the type having at least one helical screw portion attached to a polygonally shaped hub portion and having an elongated por-' tion extending from said-hub portion and a device-for installing said anchor in the earth by the utilization of rotational power and axial thrust from a mechanical power source, said device comprising.

v an elongated tubular means for housingsaid elontachment of said helical screw portion to said hub portion, said first end including means forengaging said polygonally shaped hub portion in tion.

gated portion of said anchor and having a first end:

adapted to securely engagesaid polygonally shaped hub portion of said anchor in a driving engagement and further adapted to contact a surface of said helical screw portion at a plurality of points so as to distribute said axial thrust across a portion of said surface of said helical screw portion, said first end including polygonally shaped means for engaging said polygonally shaped hub portion of said anchor in a driving engagement and means for contacting a surface of said helical screw portion in the area of attachment of said helical screw portion to said anchor to distribute said axial thrust across a portion of saidsurface of said helical screw portion. 6. A device as defined in claim 5 wherein said contacting means of said first end of said elongated tubular means comprises means for contacting said surfaceof said helical screw portion on a plurality of sides of said polygonally shaped hub portion.

7. A device for installing an anchor of the type having at least one helical screw portion attached to a polygonally shaped hub portion and having an elongated portion extending from said hub portion, in -the .earth by the utilization of rotational power and axial thrust from a mechanical power source, wherein the improvement comprises an elongated tubular means for housing saidelongated portion of said anchor and having a first end adapted to contact a surface of said helical screw portion at least at a plurality of points of said surface to thereby distribute said axial thrust along a portion of said surface of said helical screw portion and being further adapted to engage said hub portion of said anchor in a driving engagement at least partially in the area of attachment of said helical screw portion to said hub portion on a plurality of sides of said polygonally shaped hub portion, said first end including means for contacting a surface of said helical screw portion at least at a plurality of points along said surface and means for engagingsaid polygonally shaped hub portion in adriving engagement'at least partially in the area of attachment of said helical'screw portion to said polygonally shaped hub portion and on a plurality of sides of said polygonally shaped hub portion. 8. A device as defined in claim 7 wherein said contacting means of said first end of said elongated tubular means comprises means for contacting said surface of said helical screw portion on a plurality of sides of said polygonally shaped hub-portion. e 9. A method of installingan anchor of thetype having at least one helical screw portion attached toa po- 1 19 lygonally shaped hub portion and having an elongated portion extending from said hub portion, in the earth by the utilization of rotational power and axial thrust from a mechanical power source comprising the steps of engaging said hub portion of said anchor in a driving engagement with an anchor installing device at least partially in the area of attachment of said helical screw portion to said hub portion and energizing said source to install saidanchor in the earth. V

10. A method of installing an anchor of the type having at least one helical screw portion attached to a polygonally shaped hub portion and having an elongated portion extending from said hub portion, in the earth by the utilization of rotational power and axial thrust from a mechanical power source comprising the steps of placing said elongated portion of said anchor within an elongated tubular means for housing said elongated portion of said anchor, engaging said elongated tubular means with said polygonally shaped hub portion-of said anchor in a driving engagement at least partially in the area of attachment of said helical screw portion to said hub portion, and

energizing said source to install said anchor into the earth.

11. A method of installing an anchor of the type having at least one helical screw portion, a polygonally shaped hub portion and having an elongated portion extending from said hub portion, in the earth by the utilization of rotational power and axial thrust from a mechanical power source comprising the steps of engaging said hub portion of said anchor in a driving engagement with an anchor installing device, energizing said source,

applying said rotational power to said hub portion of said anchor and applying said axial thrust to said helical screw portion of saidanchor by distributing said axial thrust along at least a portion of a surface of said helical screw portion to thereby install said anchor in the earth.

12. A method as defined in claim ll wherein said step of applying said axial thrust to said helical screw portion of said anchor by distributing said axial thrust along at least a portion of said surface of said helical screw portion comprises the step of engaging said helical screw portion with said anchor installing device at least at a plurality of points of said surface of said helical screw portion.

13. A method of installing an anchor of the type having at least one helical screw portion attached to a polygonally shaped hub portion and having an elongated portion extending from said hub portion, in the earth by the utilization of rotational power and axial thrust from a mechanical power source comprising the steps of engaging said hub portion of said anchor in a driving engagement with an anchor installing device, energizing said source,

applying said rotational power to said hub portion of said anchor and applying said axial thrust to said helical screw portion of said anchor by distributing said axial thrust along at least a portion of a surface of said helical screw portion to thereby install said anchor .invthe earth, said step of engaging said hub portion of said anchor in a driving engagement with an anchor in stalling device comprising the step of engaging said hub portion of said anchor in a driving engagement with an anchor installing device at least partially in the area of attachment of said helical screw portion to said hub portion.

14. A method asv defined in claim 13 wherein said step of engaging said hub portion of said anchor in a driving engagement with an anchor installing device at least partially in the area of attachment of said helical screw portion to said hub portion comprises the step of engaging said hub portion of said anchor in a driving engagement with said anchor installing device at least partially in the area of attachment of said helical screw portion to said hub portion on a plurality of sides of said polygonally shaped hub portion.

15. A method as defined in claim 12 wherein said step of engaging said helical screw portion with said an- 

1. A device for installing an anchor of the type having at least one helical screw portion attached to a polygonally shaped hub portion and having an elongated portion extending from said hub portion, in the earth by the utilization of rotational power and axial thrust from a mechanical power source comprising an elongated tubular means for housing said elongated portion of said anchor and having a first end adapted to securely engage said polygonally shaped hub portion of said anchor in a driving engagement and further adapted to engage said hub portion at least partially in the area of attachment of said helical screw portion to said hub portion, said first end including means for engaging said polygonally shaped hub portion in a driving engagement at least partially in the area of attachment of said helical screw portion to said polygonally shaped hub portion.
 2. A device as defined in claim 1 wherein said first end of said elongated tubular means is adapted to contact a surface of said helical screw portion on a plurality of sides of said polygonally shaped hub portion.
 3. In combination, an anchor of the type having at least one helical screw portion attached to a polygonally shaped hub portion and having an elongated portion extending from said hub portion and a device for installing said anchor in the earth by the utilization of rotational power and axial thrust from a mechanical power source, said device comprising an elongated tubular means for housing said elongated portion of said anchor and having a first end adapted to securely engage said polygonally shaped hub portion of said anchor in a driving engagement and further adapted to engage said hub portion at least partially in the area of attachment of said helical screw portion to said hub portion, said first end including means for engaging said polygonally shaped hub portion in a driving engagement at least partially in the area of attachment of said helical screw portion to said polygonally shaped hub portion.
 4. The combination as defined in claim 3 wherein said first end of said elongated tubular means is adapted to contact a surface of said helical screw on a plurality of sides of said polygonally shaped hub portion.
 5. A device for installing an anchor of the type having at least one helical screw portion, a polygonally shaped hub portion and having an elongated portion extending from said hub portion, in the earth by the utilization of rotational power and axial thrust from a mechanical power source comprising an elongated tubular means for housing said elongated portion of said anchor and having a first end adapted to securely engage said polygonally shaped hub portion of said anchor in a driving engagement and further adapted to contact a surface of said helical screw portion at a plurality of points so as to distribute said axial thrust across a portion of said surface of said helical screw portion, said first end including polygonally shaped means for engaging said polygonally shaped hub portion of said anchor in a driving engagement and means for contacting a surface of said helical screw portion in the area of attachment of said helical screw portion to said anchor to distribute said axial thrust across a portion of said surface of said helical screw portion.
 6. A device as defined in claim 5 wherein said contacting means of said first end of said elongated tubular means comprises means for contacting said surface of said helical screw portion on a plurality of sides of said polygonally shaped hub portion.
 7. A device for installing an anchor of the type having at least one helical screw portion attached to a polygonally shaped hub portion and having an elongated portion extending from said hub portion, in the earth by the utilization of rotational power and axial thrust from a mechanical power source, wherein the improvement comprises an elongated tubular means for housing said elongated portion of said anchor and having a first end adapted to contact a surface of said helical screw portion at least at a plurality of points of said surface to thereby distribute said axial thrust along a portion of said surface of said helical screw portion and being further adapted to engage said hub portion of said anchor in a driving engagement at least partially in the area of attachment of said helical screw portion to said hub portion on a plurality of sides of said polygonally shaped hub portion, said first end including means for contacting a surface of said helical screw portion at least at a plurality of points along said surface and means for engaging said polygonally shaped hub portion in a driving engagement at least partially in the area of attachment of said helical screw portion to said polygonally shaped hub portion and on a plurality of sides of said polygonally shaped hub portion.
 8. A device as defined in claim 7 wherein said contacting means of said first end of said elongated tubular means comprises means for contacting said surface of said helical screw portion on a plurality of sides of said polygonally shaped hub portion.
 9. A method of installing an anchor of the type having at least one helical screw portion attached to a polygonally shaped hub portion and having an elongated portion extending from said hub portion, in the earth by the utilization of rotational power and axial thrust from a mechanical power source comprising the steps of engaging said hub portion of said anchor in a driving engagement with an anchor installing device at least partially in the area of attachment of said helical screw portion to said hub portion and energizing said source to install said anchor in the earth.
 10. A method of installing an anchor of the type having at least one helical screw portion attached to a polygonally shaped hub portion and having an elongated portion extending from said hub portion, in the earth by the utilization of rotational power and axial thrust from a mechanical power source comprising the steps of placing said elongated portIon of said anchor within an elongated tubular means for housing said elongated portion of said anchor, engaging said elongated tubular means with said polygonally shaped hub portion of said anchor in a driving engagement at least partially in the area of attachment of said helical screw portion to said hub portion, and energizing said source to install said anchor into the earth.
 11. A method of installing an anchor of the type having at least one helical screw portion, a polygonally shaped hub portion and having an elongated portion extending from said hub portion, in the earth by the utilization of rotational power and axial thrust from a mechanical power source comprising the steps of engaging said hub portion of said anchor in a driving engagement with an anchor installing device, energizing said source, applying said rotational power to said hub portion of said anchor and applying said axial thrust to said helical screw portion of said anchor by distributing said axial thrust along at least a portion of a surface of said helical screw portion to thereby install said anchor in the earth.
 12. A method as defined in claim 11 wherein said step of applying said axial thrust to said helical screw portion of said anchor by distributing said axial thrust along at least a portion of said surface of said helical screw portion comprises the step of engaging said helical screw portion with said anchor installing device at least at a plurality of points of said surface of said helical screw portion.
 13. A method of installing an anchor of the type having at least one helical screw portion attached to a polygonally shaped hub portion and having an elongated portion extending from said hub portion, in the earth by the utilization of rotational power and axial thrust from a mechanical power source comprising the steps of engaging said hub portion of said anchor in a driving engagement with an anchor installing device, energizing said source, applying said rotational power to said hub portion of said anchor and applying said axial thrust to said helical screw portion of said anchor by distributing said axial thrust along at least a portion of a surface of said helical screw portion to thereby install said anchor in the earth, said step of engaging said hub portion of said anchor in a driving engagement with an anchor installing device comprising the step of engaging said hub portion of said anchor in a driving engagement with an anchor installing device at least partially in the area of attachment of said helical screw portion to said hub portion.
 14. A method as defined in claim 13 wherein said step of engaging said hub portion of said anchor in a driving engagement with an anchor installing device at least partially in the area of attachment of said helical screw portion to said hub portion comprises the step of engaging said hub portion of said anchor in a driving engagement with said anchor installing device at least partially in the area of attachment of said helical screw portion to said hub portion on a plurality of sides of said polygonally shaped hub portion.
 15. A method as defined in claim 12 wherein said step of engaging said helical screw portion with said anchor installing device at least at a plurality of points of said surface of said helical screw portion comprises the step of engaging said helical screw portion with said anchor installing device at least at a plurality of points of said surface of said helical screw portion and on a plurality of sides of said polygonally shaped hub portion. 